The spraying of many different substances in atomized form (i.e., fine mist form) is possible using existing manually-operated devices called atomizers and vaporizers, many types of which are often small in size. The operation of these devices is straightforward. To begin with, they utilize some type of container to store the active substance either in, or suspended in, a liquid medium. When a spray is desired, an operator acts upon a control mechanism (also called a control head) in order to expel the substance out of the container. Pressure created by the control mechanism forces the substance through an atomizing nozzle which expels the atomized substance to the outside air through a small orifice.
In very general terms, the nozzle is sometimes placed on the control mechanism which is fitted to a distributor in the form of a valve or pump having an axial spray nozzle. The head may also be provided with an appropriate end piece which acts as the atomizer.
An atomizing nozzle requires some means by which a substance in its liquid form can be transformed into its atomized form. Several means exist which adequately perform this function. They generally require the use of two parts acting in concert--a core and a diaphragm. When a liquid substance is forced under adequate pressure through the nozzle, the internal axial core cooperates with the diaphragm and forms a system of turbulent channels. This turbulence effectively serves to transform the substance from its liquid to its atomized form. This model is typically assembled such that its diaphragm and core are permanently secured together. In assembling this model, the diaphragm typically is placed at the bottom of a cap. The cap is then placed over the core, as well as over the end of the nozzle, thus bringing the core and the diaphragm into permanent contact. The cap can then be permanently affixed to the nozzle by welding it thereto. Alternatively, the core is sometimes fuzed to the diaphragm before the cap is welded to the nozzle. However, regardless of exactly how the particular atomizing means is assembled, the atomizing process is carried out by two cooperating parts which are separately molded and then assembled.
The ability to effectively seal an atomizer while not in use such that no air enters and no liquid leaks therefrom is a very desirable feature from the standpoints of hygiene, preservation of the substance, and prevention of blockages due to liquid seeping through, and drying in, the nozzle between uses. There exists various types of valves which incorporate this feature, and even valves which incorporate this feature without requiring external plugs or stoppers and without interfering with the satisfactory operation of the nozzle.
One such valve providing an effective seal is described and illustrated in the French Patent FR-A-2 635 084 to Bougamont and Behar. The patent describes an atomizing nozzle having a diaphragm, a core and a valve member axially slidble within a chamber of the nozzle. On its end nearest the nozzle's orifice, the valve member has a concave circular cup in which the flexible edges of the cup are turned toward the orifice. On its end farther from the nozzle's orifice, the valve member has a stem which provides the member with its lateral guidance. When the nozzle is not in use, the edges of the cup block the passage through the nozzle chamber thus making the seal. And because the valve member remains axially mobile, it can adapt freely to any slight pressure variations to which it can be exposed, thereby maintaining an effective seal during the non-use period.
In this particular valve system, however, the core used to form turbulent channels and the valve member are two separate parts. And although the patent discloses that the nozzle can optionally be assembled in such a way that the core and valve member are secured together, this configuration would eliminate the valve member's axial mobility. In this latter option, therefore, the edge of the valve would appear to function in a less satisfactory manner, the sealing being less precise and less durable.